A 3GPP long term evolution-advanced (LTE-A, LTE-Advanced) system uses a relay coordinated transmission method to improve quality of service for users at cell edges and expand the cell coverage. The capacity of a backhaul link of a relay network limits throughput of an access link. Therefore, it is crucial to enhance quality of the backhaul link. In a backhaul link of a relay network having multiple relay stations (Relay), multiple relay stations share the same channel resources, and the multiplexing gain can improve system capacity greatly. However, co-channel interference is inevitable when the multiple relay stations share the same resources.
To cancel co-channel interference, at present, an known solution with optimal capacity is dirty paper coding (DPC, Dirty Paper Coding), but it is difficult to implement the solution due to its high complexity. In addition, a coordinated multi-point transmission/reception (CoMP, Coordinated Multipoint Transmission/Reception) technology attracts wide attention and is researched in the industry in recent years because it can effectively improve performance of users at cell edges and improve system throughput, but the CoMP technology requires coordination between base stations of multiple cells, and there is still a difficulty in actual applications.